Safety stop for traveling structures



Sept. 6 1927.

A. F. CASE SAFETY STOP FOR TRAVELING STRUCTURES Filed Auz. so, 1924 a Sheet S-Sheet 1 INVENTLTH A a? 1. 3 M

I A'I'T'annmr in mm @m m.

Sept. 6, 1927.

A. F. CASE SAFETY 'STOP FORTRAVELING STRUCTURES 3 Sheets-Sheet 2 Filed Aug. 50. 1924 awvemto'c Sept. 6, 1927. A F CASE 1,734

SAFETY STOP FOR TRAVELING STRUCTURES Filed Auz. 30. 1924 3 Sheets-Sheet 5 nvento'a Patented Sept. 6,1927.

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ARTHURF. casn, or CLEVELAND, OHIO,'ASS1'GNOR TO THE wE LL aN-sEAvna-Mom GAN COMPANY, or CLEVELAND, OHIO, A coaronarrou'or'oruo.

SAFETY STOP FOR TRAVELING STRUCTURES,

Application filed August 30, 1324;. 'SerialNo. 735,162. 7 i f This invention relates to what may be termed a safety stop for structures adapted to travel along a trackway, and has particular. reference to a safety stop for material conveying bridges, to hold the structure against movement by wind pressure on it.

Large traveling bridges have on more than one occasion been wrecked by. being impelled along the trackway bywind pressure notwithstanding the application of friction brakes, and to avoid wreckage of traveling structures such as these bridges, track clamps have been provided, two or more of which have been secured to each supporting leg of the bridge, these clamps consisting of pairs of jaws which aredesigned to set by .counterweights to frictionally engage opposite sides of the rails, and to be released by power usually derived from one or more electric motors which lift the counterweights and thus disengage the aws from the track rails when the structure 18 to be moved along the track.

Such clamps have not proven to be en tirely satisfactory, for bridges are known to have been wrecked notwithstandingthe fact that they were equipped with a'series of the rail engaging clamps which though set to engage the rails as tightly as the nature of the apparatus permitted, were not effectiveto hold the structure against drifting along the trackway under the pressure of an unusually heavy wind. Furthermore, aside from the fact that such clamps do not afford absolute protection, they are as a rule very complicated by reason of the fact that they involve a great deal of apparatus in the way of cables, sheaves and hoists scattered 4 throughout the structure and extending from the lower portions of the supporting legs up to and along the bridge proper to the point where the clamps are designed to be controlled. Because of all this apparatus used in conjunction with the. car clamps themselves, and required for their operation, the clamps often get out of order and for that reason are unreliable.

In my co-pending application, Serial No. 554,080, filed April 17, 1922, there is dis closed a safety stop for traveling bridges .in which more effective means is provided for holding the bridge structure from movement along the trackway, this stop device consisting of a plurality of wheel blocking units each carrying an actuating motor,

which are loosely suspended from the sill of the bridge in such manner that they may be supported out of contact with the rails and wheels or lowered by gravity onto the rails, these units each having a wheelblocking wedge and clamps which automatically grip therail. to prevent slippage ofthe wedges upon. the rail after the wedges have been lowered upon the rails, the loose connection between the wedges and sill being such that the bridge structure v may have suflicient movement with respect to the wedges to permit the wheels to roll'up into engagement with the oppositely disposed wedges.

The present invention is an improvement over the device disclosed in my co-pending application above referred to and has for its object to simplify the operating mechanism and lessen the cost of manufacture thereof. More specifically it is the object of the present invention-to provide a mechanism in which a single motor may be employed for operating several wheel blocking units.

The present invention provides wheel blocking units comprising wedges engageablebetween the wheel and rail, clamps for holding the wedges against movementalong the rails, counterweights for setting the clamps, and actuating members associated with the units adapted to be connected with an operating mechanism mounted upon the frame of the bridge for releasing the clamps and shifting the wedges out of contact with the wheels and rails. I Y 7 .With the above and other objects in view, the invention maybe said vto comprise the device as illustrated in the accompanying drawings hereinafter described and particularly set forth in the appended claims, together with such variations and modifica- ',tions thereof as shall beapparent to one skilled in the art to which the invention appertains. I

Reference should be. had to the accompanying drawings forming a part of this specification in which Fig. 1 is a side eleva-' tion showinga portion of the bridge, with one of thewheelblocking units,,the operatingmotor and the connections from the motorito the unit, Fig, 2 is a diagrammatic side elevation of the bridge sill showing'th'e arrangement of the blocking units with respect to the supporting wheels; Fig. 3 is a side elevation of a wheel blocking unit showing the same in elevatedposition; Fig. 4 is a top plan view of the actuatin motor and the gearing associated therewith; Fig. 5 1s a detail view showing a side elevation of the solenoid clutch controlling the connection between'the motor and the crank arms which actuate the wheel blocking units; Fig. 6 is a vertical section through a wheel blocking unit showing the clamps associated therewith; Fig. 7 is a detail view of the pawl and ratchet associated with the actuatlng mechanism; Fig. '8 is a wiring diagram showing the motor and solenoid circuits Referring to the accompanying drawings, the sill of the bridge which extends longitudinally of the supporting rails and upon which the operating mechanism is mounted is designated by the reference numeral 1 and the supporting wheels which are carried by suitable trucks spaced longitudinally of i the sill are indicated by the reference numeral 2. As shown in Fig. 2 of the drawing, a wheel blocking unit is associated with the rear wheels of each truck at the rear end of the sill, and with the front wheels of each truck at the front end of the sill, the forward wheel blocking units being in front of the wheels with which they cooperate and the rear wheel blocking units being at the rear of the wheels with which they cooperate, in order to prevent movement of the bridge in either direction.

The wheel blocking units are all identical in construction and each has a body portion 3 in the form of a casting which is adapted to rest upon the top surface of the track rail, the casting 3 being provided at its forward end with a wedge shaped portion 4 which has a curvature corresponding sub stantially to the curvature of a supporting wheel 2. At its rear end casting 3 is pro vided with integral positioning lugs 5 which are adapted to engage with opposite sides of the rail to prevent lateral movement of the -casting with respect to the rail and adjacent its forward end, the casting carries a pair of clamping jaws 6 which are pivoted upon opposite sides thereof adjacent the lower edge of the casting on hori zontally disposed pivoted pins 7. The clamping aws 6 have short rail engaging portions below the pivots 7 and extend upwardly to above the top of the casting 3, the upper ends of the jaws 6 having pivotally connected thereto toggle links 8 which extend inwardly therefrom and are, connected by ball and socket "joints with the forward end of a counterweighted lever 9, which serves to shift the clamping jaws into and out of clamping en gagement with the rail. The counterweight lever 9 is pivoted intermediate its ends between bearing standards 10 formed integrally with casting 3 andprojecting upwardly therefrom, apivot pin 11 extending through the upper ends of the standards 10 and through the lever 9. The lever 9 has a counterweight 12 attached to its rear end, which serves to normally hold the forward end of the lever in elevated position and through the togglelinks 8 to hold the jaws 6 in tight clamping engagement with the rail. In order to provide a longer lever arm the counterweight 12 may be provided with a slot 13 extending inwardly from its rear end to receive the adjacent wheel '2 so that the wheel will not interfere with the movements of the counterweight lever. For lifting the counter-weighted end of the lever 9 to release the clamping jaws, the casting 3 is provided with a rear bearing standard 14 upon which is pivotally mounted a double bell crank lever, which has a forwardly extending arm 15 which carries a roller 16 engageable with the under side of the lever 9 at the rear of its pivot 11. The bell crank lever has a rearwardly extending arm 17 and a longer upwardly extending arm 18 which is connected by a link 19 with a crank arm 20 fixed to transversely extending crank shaft 21. By turning the crank shaft 21 the bell crank may be rocked to swing the forwardly extending arm 15 upwardly to lift the counterweighted end of the lever 9 and release the clamps.

Means is provided for suspending the wheel blocking units from the sill of the bridge in such manner that actuation of the clamp releasing means by the crank arms 20 will also cause the units to be lifted out of engagement with the track rails and to swing out of contact with the wheels. A forward suspension link 22 is pivotally connected to the lever 9 adjacent the forward end thereof and to the sill 1, the link 22 being provided with a turn buckle 23 by means of which its length may be adjusted and being connected to the sill 1 by means of a pin 25 fixed to the sill and projecting through an elongated slot 24 in the upper end of the link, a rear suspension link 26, similar to the link 22, is pivotally connected at its lower end to the rear end of the rearwardly extending arm 17 of the bell crank actuating lever and at its upper end to the sill of the bridge, the rear link 26 being provided with a turn buckle 27 and connected to the sill by means of a pin 28 fixed to the sill and extending through an elongated slot 29 in the upper end of the link.

When the casting 8 is resting upon the track with which they cooperate.

the rails and the bridge may be moved freely in either direction the slight distance necessary to permit the supporting wheels to move on to either the rear blocking wedges or the oppositely disposedfront blocking wedges, such movements of the bridge having no tendency to shift the blocking units along the rail, or to release the clamps. Thus when the blocking units are clamped to the rails the thrusts are transmitted directly from the wheels to the blockingunits and through the units to the rail instead of through the frame to the clamps.

When the crank arms 20 are actuated to releasethe rail clamps, the rearwardly projecting arm 17 of the bell crank is moved downwardly and the forward end of the lever 9 causing the clamps to be released from the rail and the simultaneous downward movements of the arms 17 and the forward end of the lever 9 causing the links 22 and 26 to be-drawn downwardly until the pins-24 and 28 are engaged with the upper ends of the slots and 29, continued movement causing the units to be lifted from the rails. The links 22 and 26 are inclined forwardly with respect to the units to which they are secured, so that the pull on the long arm 18 of the bell crank through the link 19 connected to the crank arm 20 is in a direction to swing the links 22 and 26 rearwardly to simultaneously elevate the units and swing the same away from the wheels The pivotal movement of the bell crank actuating lever is limited by a vertically adjust-able stop 30 at the rear end of the casting 3, which is engaged by the rearwardly extending arm 17 of the lever in its downward movement. When the bell crank actuating lever has been shifted until the arm 17 engages with the stop 30, the clamping jaws 6 will be opened and continued movement of the actuating crank arm 20 will swing the links 22 and 26 about their pivots to move'the unit clear of the supporting wheel with which itcooperates and clear of the rail so that the bridge is free to travel along the trackway.

It is to be understood that the wheel blocking un ts, as shown in Fig. 2 are duplicated upon the opposite of the bridge, each ofthe crank shafts 21 extending transversely to the opposite sill for operating the wheel block ing units cooperating with the opposite rail of the trackway. Means are provided for simultaneously actuating all of the wheel blocking units and this means consists of an electric motor centrally mounted .upon the bridge frame and having connections for simultaneously operating the crank shafts 21 to release the clamps and elevate the blocking units to free the same from the rails and wheels. The electric motor 31, which is centrally mounted upon the sill '1 of the bridge structure, is provided with a shaft 32 which extends into the gear casing 33 which houses the reduction gears, the

casing 33 having fixed thereto outside the casing a small spur gear 34 which meshes with the large spur gear 35 fixed to the transverse shaft 36. Through the gearing above described the shaft 36 is continuously driven during the operation ofthe motor and means is provided for operating the crank shafts 21 from the shaft 36 to simultaneously move the blocking units to releasing position. shaft 36, adjacent the outer end thereof, is a clutch hub 37 which has oppositely extending crank arms 38 and 39 and the hubadapted to be secured to the shaft--36 to rotate therewith, by means of a shiftable clutch member 40 which is slidably keyed to the shaft and movable into and out of en gagement with the clutch hub 37. The clutch member 40 is operated by means of a bell crank shifter 41, one arm of which engages with the hub member and the other arm of which is connected to a solenoid actuator 42; When the solenoid 1s energized the core thereof is drawn upwardly and the clutch member 40 is held in engage- VVhen the solenoid ment with the hub 37 circuit is broken, the solenoid core drops by gravity and shifts the clutch member 40 out of engagement with the hub 37. Links 43 and 44 are suspended from the outer 'ends of the arms 38 and 39 and are connected at their lower ends to hell cranks 45 and 46,

shaft of one of the driven gears within the i Loosely mounted upon the which are pivoted upon shafts fixed to the sill, the opposite arms of the bell cranks 45 and 46 being connected to oppositely extending connecting rods 47 and 48 which are and 48. The crank arms 49 connected to the shafts 21, through which the forward wheel blocking units are operated, are disposed at an inclination opposite thatof the crank arms 49 connected to the shafts 'throi'igh which the rear wheel blocking units are operated, so that by aturning movement of the'crank arms 38 and 39,in a direction to shift the rods 47 and 48 towards each other all of the wheel blocking units maybe snnl'iltaneously lifted, the rods 47 and 48 being under tension during the lift'ng movement.

The solenoid 42 is energized at all times,

except when it is de-energized to permitthe wheel blocking units to move by gravity to rail engag'ng position, the solenoid serving to hold the clutch member 40 in engaging position to connect th'e'crank arms 38 and 39 to the shaft 36, so that they may be actuated by the motor to elevate the wheel blocking units, the solenoid device serving to retain the clutch in engagement after the motor has been stopped, to retain the wheel blocking units in elevated position. The motor 31 is driven in one direction only and to prevent reverse rotation of the rotor by the weight of the wheel blocking units acting through the linkage connecting the same to the arms 38 and 39, the gear 35 has fixed to the inner face thereof a ratchet 51 which is engaged by spring pressed pawl 52, the teeth of the ratchet being so disposed as to prevent rotation of the gear 35 in a direction reverse to that in which it is driven by the motor.

The motor is preferably controlled from a main switch, located at a convenient point on the bridge structure which is held closed while the blocking units are held in elevated position and held open while the units are engaged with, and the motor circuit is also actuator 53 has spaced upwardly extending arms 54 and 55 which are adapted to be alternately engaged by a pin 56 carried by the rod 58 during the forward and return movements of the rod.

The actuator 53 is so placed with respect to the pin 56 that the pin 56 engages the 'arm 54 during movementof the rod in a direction to elevate the wheel blocking units and shifts the actuator member 53 to a position in which the motor circuit is opened, the

.opening of the motor circuit being so timed that the motor is stopped when the wheel blocking units have reached their uppermost positions. The solenoid 42 which is so connected across the motor circuit as shown in Fig. 7 that it is not affected by the cut-out switch operated by the actuator 53 remains energized and holds the "clutch 40 in engaging position, locking the arms 38 and 39 to the shaft 36 and since the pawl 52 prevents reverse rotation of the shaft 36, the wheel blocking units will be retained in elevated position.

Whenever the main circuit is broken or the supply of current thereto fails, the looking units will be released and will automaticallv move to blocking position to hold'the bridge against movements along the trackway, the solenoid circuit being at the same time broken to release theclutgh member 40 whereupon the wheel blocking units will'be lowered by gravity into engagement with the rails and upon engagement with the rails the clamping jaws 6 will be set by the counterweighted lever 9. In order to retard the gravity movements of the wheel blocking units, and to gradually shift the-clamps into rail gripping positions means is provided for retarding the movements of the actuating cranks 38 and 39 under the weight of the Wheel blocking units. To this end, the clutch hub 37 has a third crank arm 57, to the outer end of which is pivotally connected piston rod 58, which extends into a dash pot cylinder 59, the dash pot serving to retard the rotary movements of the arms 38 and 39 upon their release from the operating shaft WVhile the bridge is being moved along the trackway the main solenoid and motor controlling switch will be closed and the cutout switch open so that the wheel blocking units will be held in elevated position by the solenoid operated clutch and by the pawl 52 which prevents reverse rotation of the shaft 36. After the bridge has been stopped the main switch is opened breaking the solenoid circuit, thereby disengaging the clutch member 40 from the clutch hub 37 carrying the crank arms 38 and 39, leaving the wheel blocking units free to descend by gravity, the downward movement being retarded by the dash pot 59, the return movement of the actuating rod 48 shifts the cut-out switch actuator to the position in which the said switch is closed so that when the main switch is again closed the motor will be operated.

When it is desired to release the bridge, to permit it to travel along the trackway, the circuit of the motor 31 will be closed by closing the main cont-roller switch and the motor will operate until the crank arms 38 and 39 have been turned through a suiiicient angle to release the clamping jaws 6 and elevate the wheel blocking units of the engagement with the rails and wheels, the actuator 53 being engaged by the pin 56 to break the motor circuit after the wheel blocking units have been moved to inoperative position. Upon the return movement of the connecting rod 48, during the gravity movement of the wheel blocking units, the arm 55 of the actuator is engaged by the pin 56 shifting the actuator 53 to its original position in which the auxiliary switch is closed and the arm 55 is in the path of movement of the pin 56, so that when the stop members are again elevated the actuator 53 will be moved to a position to deenergize the motor. 7

Having described my invention, 1 claim: 1. The combination with a traveling structure adapted to be moved along a trackway, of oppositely disposed wedge members fleX- ibly suspended from the frame of said structure, each adapted to move by gravity into blocking position between a wheel and a rail, an operating means carried by the frame,

and means connecting the operatingwmeans to the wedge members or simultaneously shifting the same out of blocking position.

2. The combination with a traveling structure adapted to be moved along a traclrway,

of a plurality of wheel blocking units each com risin a rail en 'a in wed e member 2% b a: a,

and a'pairof rail clamping jaws carried by the wedge members, means'for suspending said units from said structure out of engagement with said rails and for holding said .jaws in open. position, said means in eluding a releasable retaining element, and gravityflactuated means for causing said jaws to grip. the rails after said retaining element is released.

3. Thecombinationwith a traveling structure adapted tobe moved along a trackway, of a plurality 'of wheel blocking units each comprising a wedge. adapted to be positioned between a wheel and rail, a rail engaging clamp carried by thewedge and a-counterweight for setting-the clamp, an actuating meansonthe frame-of said structure, and connectronsfrom said actuating member to said counterweight. for simultaneously releasing the clamps.

l. The combination with a traveling struc ture adapted to be moved along a trackway, of I oppositely disposed wheel blocking wedges, links suspending said wedges from the frame of said structure, said links being arranged to permit each wedge to move by gravity into a position between a wheel and "rail, an operating member on said frame, and means connecting the said operating member to said blocking units to move the wedges away from the wheels and the rall- .1 I I i i 5; The combination with a traveling structure adapted to be moved along a trackway, of a plurality of wheel blocking'units suspended from the structure and adapted to move by gravity to rail engaging position,

actuating mechanism connected to said units for simultaneously lifting the'same out .of

' releasing said clamp. I

. 7. A safety stop for traveling structures comprising a member engage'able with a rail of the trackway, a rail clamp carried by said member,movable clamp actuating mem-. bers carried by saidmember, means on the frame ofsaid structure connected to said actuating members to operate the clamp, and.

means operated by the acuating members for raising and lowering the clamp.

8; safety stop for traveling structures comprlslng a member engageable wlth a rail.

of the. trackway, a rail clamp carried by said member, clamp actuating means including a counterweight connected to the clamp to set thesame, a motor mounted on the" frame ofysaid structure, connections from. said motor to said clamp actuating means j to release the clamp, and means operated by.

the clamp actuating means for raising and lowering the said rail engaging member.

9. A safety stop for traveling structures,

comprising a rail engaging member, a rail clamp carried thereby, clamp actuating means carried by'said member including a lever having a counterweight thereon and s0 connected to the clamp that the counter-.

weight acts to set the clamp, an actuating lever pivoted to said member and engaging the counterweight lever, and means. for

moving said actuating lever in a direction,

to releasethe clamp."

10. safety stop for traveling structures comprising a rail engaging member, a railv clamp carried thereby, a lever carried bysaid member and connected to said clamp to operate the same, said lever having a counterweight which acts to set the clamp, a lever pivoted to said member and engage able with said counterweight leverto move the same in a direction to release said clamp,,

and a pair of suspension members, one connected to the frame of said structure and to said; counterweight lever and the other to the frame andto said actuating lever. 11. The combination with. a traveling structure adapted to be moved along a track.- way, of a plurality of wheel blocking units suspended from the frame of said structure having rail engaging clamps, clamp actuating means carried by the units, including counterweights-carriedby the units for setting the elamps, a movable actuating, mem-v ber on the frame connected to said clamp actuating means, and means operatedby.

said clamp actuating means for lifting the;

units. i v i 12.. The combination with a traveling structure adapted to be moved along a trackway, of a plurality of wheel blocking units suspended from the frame of the structure, a motor on the frame and connections,

from said motor to. said units for elevating the same, releasable means for retaining said units. in elevated position, said units being movable by gravity to rail engaging position when released, and means for retarding the'gravity movements of the units.

-13. The combination with a traveling structure adapted to be moved along a. trackway, of a plurality of wheel blockin units flexibly suspended from the frame of said structure, a motor on said frame and means operated thereby for simultaneously elevating the units, and means acting upon the motor operated means for retaining the units in elevated position.

14. The combination with a traveling structure adapted to be moved along a track way, of a plurality of wheel blocking units flexibly suspended from the frame, an electric motor, a shaft adapted to be driven by the motor, means for preventing rotation of the shaft in one direction, an operating member loosely mounted on said shaft and connected to said units for simultaneously elevating the same, and releasable means for connecting said operating member to the shaft. 7 o r 15,. The combination with a traveling structure adapted'to be moved along a trackway, of a wheel blocking unit comprising a 'Wedge member adapted to be interposedbetween a wheel and rail, a rail engaging clamp carried by the wedge member, a counterweight for setting the clamp, an operating shaft on the frame of said structure, means connectin said shaft to said unit to lift the same release the clamp in opposition to the counterweight, and means for releasing said unit from'the shaft to permitthe unit to move by gravity-to rail engaging position and to permit said counterweight to set the clamp.

16. The combination with a traveling structure adapted to be movedalong a trackway, of a wheel blocking unit suspended from the frame of said structure which is engageable with the track. rail and has a clamp adapted to grip the rail, a counterweight for setting the clamp, an actuating member on the unit for shifting the counterweight to release the'clamp, an actuating member on the frame connected with said first mentioned actuating member to operate the same, and means operated by said first mentioned actuating members for'shifting the unit out of engagement with the rail.

17 The combination with a traveling structure adapted to be moved along a trackway, of a wheel blocking unit suspended from the frame of said structure and engageable with a track rail, an operating shaft on said frame, means for driving said shaft in one direction and for preventing rotation thereof in the opposite direction, an operating member loosely mounted on said shaft, means connecting said operating member to the unit, releasable means for connecting said operating member to the shaft, and means for imparting a predetermined rotative movement to the shaft to lift the unit out of rail engaging position. v v

18. The combination with a traveling structure adapted to be moved along a trackway, of a wheel blocking unit engageable with the trackway and having a'clamp for pre-' venting movement thereof along the trackfromthe rail and to y: mp actuating members carried by I bers, and means connecting the said frame to the actuating members on the unit for' lifting the unit out of contact with the-rail upon the movement of said actuating mem-- bers to release the clamp.

19. A safety stop for traveling structures comprising a wedge member engageable with the trackway and adapted to be positioned between a wheel and rail, clamping jaws car ried by said wedge member, a counterweight lever connected to-said jaws,:and a second lever carried by the wedgemember and engageable with the first lever tomove the same I in opposition to the counterweight.

20. A safety stop for traveling structures comprising a wedge member engageable between a wheel and rail, clamping jawscarried by said wedge member and engageable with the rail to hold the wedge member against movement longitudinally of the rail, a counterweighted lever pivoted upon: the wedge member and connected to the clamping ]1WS to operate the same, a'lever pivoted upon the wedge member and engageablewith the first mentioned lever to shift the same. in

opposition to the weights, and means flex to be moved along a trackway comprising a wheel blocking member having means engageable with a part of the trackway to hold the same against longitudinal movement on thetrackway, and adjustable links connecting said member to the frame ofsaid structure. v v

22; A safety stop for traveling structures adapted to move'along a trackway comprising a wheel blocking member, means carried by said member for securing-the same to the trackway, and means connecting saidmemher and frame for releasing said blocking member from the trackway and lifting the same out of engagement therewith, said; connecting means permitting movement of the structure relative to the blocking mem ber when said blocking member is secured to the trackway.

23. A safety stop adapted to travel along a trackway compris' ing oppositely disposed wedges each adapted for traveling structures relative to the blocking Wedges in either for setting the clamp, and means operated direction when the wedges are in blocking by the clamp setting means for releasing the positions. Wedge from said structure. 7 10 24. A safety stop for traveling structures In testimony whereof, I hereunto aflix my comprising a Wedge member adapted to be signature. I

positioned between a wheelrand rail, a rail engaging clamp carried by the Wedge, means ARTHUR F.- CASE. 

